<template>
  <view>
    <view class="search-box">
      <!-- 基本用法 -->
      <uni-search-bar @input="input" v-model="kw" :radius="100" clearButton="auto" cancelButton="none"></uni-search-bar>
    </view>
    <!-- 搜索建议列表 -->
    <view class="sugg-list" v-if="searchResults.length !== 0">
      <view class="sugg-item" v-for="(item, index) in searchResults" :key="index" @click="gotoDetail(item)">
        <view class="goods-name">{{item.goods_name}}</view>
        <uni-icons type="arrowright" size="16"></uni-icons>
      </view>
    </view>

    <!-- 搜索历史 -->
    <view class="history-box" v-else>
      <!-- 标题区域 -->
      <view class="history-title">
        <text>搜索历史</text>
        <uni-icons type="trash" size="17" @click="clean"></uni-icons>
      </view>
      <!-- 列表区域 -->
      <view class="history-list">
        <uni-tag :text="item" v-for="(item, index) in histories" :key="index" @click="gotoGoodsList(item)"></uni-tag>
      </view>
    </view>
  </view>
</template>

<script>
  export default {
    onLoad() {
      this.historyList = JSON.parse(uni.getStorageSync('kw') || '[]')
    },
    data() {
      return {
        // 防抖节流
        timer: null,
        kw: '',
        // 搜索结果列表
        searchResults: [],
        // 历史搜索
        historyList: []
      };
    },
    methods: {
      // 触发输入事件
      input(e) {
        // 防止输入框没输入一次就发一次请求，这样做在五百毫秒以内输入文字将不会发起请求
        clearTimeout(this.timer)
        this.timer = setTimeout(() => {
          // console.log(e.value)
          this.kw = e.value
          this.getSearchResults();
        }, 500)
      },

      // 获取搜索结果列表
      async getSearchResults() {
        // 先判断关键词是否为空
        if (this.kw === '') {
          this.searchResults = [];
          return
        } else {
          const {
            data: res
          } = await uni.$http.get('/api/public/v1/goods/qsearch', {
            query: this.kw
          })
          if (res.meta.status !== 200) return uni.$showMsg()
          this.searchResults = res.message
          this.saveSearchHistory();
        }
      },
      // 点击列表跳转到对应的商品页
      gotoDetail(item) {
        console.log(item)
        uni.navigateTo({
          url: "/subpkg/goods_detail/goods_detail?goods_id=" + item.goods_id
        })
      },
      // 将输入的信息加入搜索历史
      saveSearchHistory() {
        // this.historyList.push(this.kw)
        const set = new Set(this.historyList);
        set.delete(this.kw)
        set.add(this.kw)
        this.historyList = Array.from(set)
        // 对搜索历史的数据进行持久化存储
        uni.setStorageSync('kw', JSON.stringify(this.historyList))
      },
      // 清空历史记录
      clean() {
        this.historyList = []
        uni.setStorageSync('kw', '[]')
      },
      // 点击搜索历史跳转到商品列表页面
      gotoGoodsList(item) {
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?query=' + item
        })
      }
    },
    computed: {
      histories() {
        return [...this.historyList].reverse()
        /**
         * 解决搜索历史重复的代码简化
         * 前提：在 saveSearchHistory 方法中的内容代码是
         * this.historyList.push(this.kw)
         */
        // return [...new Set([...this.historyList].reverse())]
      }
    }
  }
</script>

<style lang="scss">
  .search {
    position: sticky;
    top: 0;
    z-index: 999;
  }

  // 输入列表
  .sugg-list {
    padding: 0 5px;
  }

  .sugg-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 12px;
    padding: 13px 0;
    border-bottom: 1px solid #efefef;
  }

  .goods-name {
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  // 搜索历史
  .history-box {
    padding: 0 10px;
  }

  .history-title {
    display: flex;
    justify-content: space-between;
    height: 40px;
    align-items: center;
    font-size: 13px;
    border-bottom: 1px solid #efefef;
  }

  .history-list {
    display: flex;
    flex-wrap: wrap;
  }

  .uni-tag {
    margin-top: 5px;
    margin-right: 5px;
  }
</style>